Unix Commands Work on Server But Not in Ruby Ssh Session

Net::SSH with non unix/linux host?

I assume it works fine when you login in the shell manually.

To understand what is the difference when you connect through net/ssh collect output of env command in both cases and compare.

That most probably you'll see a difference that will lead you to a solution or at least will give you dirty trick.

UPDATE. (Not working)

Net::SSH.start('10.204.121.192', 'password', :password => "password") do |ssh|
   ssh.open_channel do |channel|
        channel.on_data do |ch, data|
          puts "got data: #{data.inspect}"
        end
        channel.send_data("INH-MSG-ALL;\n")
   end
end

UPDATE2. (Working)

Net::SSH.start('10.204.121.192', 'password', :password => "password") do |ssh|
   ssh.open_channel do |channel|
        channel.send_channel_request "shell"
        channel.on_data do |ch, data|
          puts "got data: #{data.inspect}"
        end
        channel.send_data("INH-MSG-ALL;\n")
   end
end

How to SSH interactive Session

Something like this?

Net::SSH.start('10.0.0.6', 'not_root', :password => "test") do |ssh|
   ssh.open_channel do |channel|
      channel.on_request "exit-status" do |channel, data|
        $exit_status = data.read_long
      end
      channel.exec("passwd") do |channel, success|
        if success
          channel.on_data do |channel, data|
            # Don't really need this callback actually
            puts "got data: #{data.inspect}"
          end
          # You don't need this line if you're root
          channel.send_data("oldpass\n")
          channel.send_data("newpass\n")
          channel.send_data("newpass\n")
        else
           puts "FAILED"
        end
      end
      channel.wait
      puts "SUCCESS" if $exit_status == 0
   end
end

This one is dirty, but working for both upon premature on-expiration prompt and upon passwd issuing:

Net::SSH.start('localhost', 'not_root', :password => "test") do |ssh|
  ssh.open_channel do |channel|
     channel.on_request "exit-status" do |channel, data|
        $exit_status = data.read_long
     end
     channel.on_data do |channel, data|
        puts data.inspect
        if data.inspect.include? "current"
                channel.send_data("oldpass\n");
        elsif data.inspect.include? "new"
                channel.send_data("newpass\n");
        end
     end
     channel.request_pty
     # This will just safely fail if we have already a password prompt on
     channel.exec("passwd");
     channel.wait
     # Will reflect a valid status in both cases
     puts $exit_status
  end
end

How can i execute 2 or more commands in the same ssh session?

see if there's something analogous to the file(utils?) cd block syntax, otherwise just run the command in the same subshell, e.g. ssh.exec "cd /var/example/engines/; pwd" ?

How to execute instructors in order with ruby net ssh channel?

Use sync shell service for it, do something like:

Net::SSH.start( 'localhost' ) do |session|
  shell = session.shell.sync
  shell.touch 'a.file'
  shell.mv 'a.file', 'b.file'
  shell.send_command("rm", 'b.file')
  shell.exit
end

or just organize the commands on-a-line:

work session, "touch a.file; mv a.file b.file; rm b.file"

Net::SSH::Multi using the session.exec, how do you get the output straight away? Ruby

Adding session.loop after session.exec allows the program to wait for the output.

Such as:

session.exec(command)do |ch, stream, data|
  puts "[#{ch[:host]} : #{stream}] #{data}"
end

session.loop
# Or session.wait also does the same job.

What is the cleanest way to ssh and run multiple commands in Bash?

How about a Bash Here Document:

ssh otherhost << EOF
  ls some_folder; 
  ./someaction.sh 'some params'
  pwd
  ./some_other_action 'other params'
EOF

To avoid the problems mentioned by @Globalz in the comments, you may be able to (depending what you're doing on the remote site) get away with replacing the first line with

ssh otherhost /bin/bash << EOF

Note that you can do variable substitution in the Here document, but you may have to deal with quoting issues. For instance, if you quote the "limit string" (ie. EOF in the above), then you can't do variable substitutions. But without quoting the limit string, variables are substituted. For example, if you have defined $NAME above in your shell script, you could do

ssh otherhost /bin/bash << EOF
touch "/tmp/${NAME}"
EOF

and it would create a file on the destination otherhost with the name of whatever you'd assigned to $NAME. Other rules about shell script quoting also apply, but are too complicated to go into here.

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